Nine conservation groups and 16 South Carolina coastal communities are expected to sue the Trump administration Tuesday to stop leases to explore for natural gas and oil offshore.

Tracts off South Carolina are among the waters up for grabs. The groups said they will file two separate lawsuits, both in U.S. District Court in Charleston.

The lawsuits will claim the leases violate the federal Marine Mammal Protection Act, which prohibits harassing or killing animals such as whales or dolphins.

The exploration would include seismic blast testing that involves loud airguns considered harmful to marine mammals and other sea life.

"Ignoring the mounting opposition to offshore drilling, the decision to push forward with unnecessary seismic testing violates the law, let alone common sense," said Charleston-based attorney Catherine Wannamaker, with the Southern Environmental Law Center.

"An overwhelming number of communities, businesses and elected officials have made it clear that seismic blasting — a precursor to drilling that nobody wants — has no place off our coasts," she said.

The 16 municipalities are Charleston, Mount Pleasant, Isle of Palms, Folly Beach, Edisto Island, Seabrook Island, Kiawah Island, James Island, Beaufort, Hilton Head Island, Bluffton, Port Royal, Awendaw, Pawleys Island, Briarcliffe Acres and North Myrtle Beach. Also part of the litigation is the S.C. Small Business Chamber of Commerce.

The South Carolina Environmental Law Project sued on their behalf.

“We are disappointed that the National Marine Fisheries Service authorized serious impacts to the critically endangered right whale, along with hundreds of thousands of other species of marine life, in order to allow for unnecessary seismic blasting," said attorney Amy Armstrong with the legal group.

"The coast has spoken loudly and repeatedly against seismic airgun surveying and offshore drilling. But the current administration refuses to listen. I hope that the courts agree with us that this activity is unnecessary and illegal," she said.

The International Association of Geophysical Contractors, which represents exploration companies, declined to comment on the lawsuits.

The law center is suing on behalf of South Carolina Coastal Conservation League, North Carolina Coastal Federation, One Hundred Miles and Defenders of Wildlife. Other groups participating in the lawsuit are Oceana, the Natural Resources Defense Council, Earthjustice on behalf of Surfrider Foundation and the Sierra Club and the Center for Biological Diversity.

The legal salvo has been anticipated. Center attorneys said in late November they were looking at all available options to challenge these permits and that "obviously a lawsuit is an available option."

In November, federal regulators released a long-awaited final authorization for the seismic tests under the Marine Mammal Act, which allowed for incidental harassment so long as some precautions were taken. It was the final step needed for the federal Bureau of Ocean Energy Management to lease the waters to the exploration companies.

President Donald Trump has sought the move since January. It has been opposed by millions of coastal residents and groups, as well as a number of leading Republicans and Trump supporters along the coast, including S.C. Gov. Henry McMaster, a Trump ally.

After huddling with McMaster last week, S.C. Attorney General Alan Wilson on Monday announced he would send a letter to Interior Secretary Ryan Zinke, who directs the agencies involved. Attorneys general representing 12 other states did that in February.

It will be up to nine companies to follow up on requested permits to explore any or all of five zones from mid-Florida to the Northeast. Five of the companies want to search off of South Carolina's coast, where massive opposition has arisen from communities, leaders and politicians.

In seismic testing, exploration companies survey for fossil fuels in the ocean bottom by detonating sound blasts from airguns that can deafen, injure and scatter marine animals, according to studies by the federal government and other groups.

The findings are then sold to oil companies.

For the tests, the powerfully loud guns are fired underwater every 16 seconds to read “echoes” from the bottom geology. The tests take place over miles of ocean for months at a time.

Industry representatives say advances in drilling technology have made the operations safer, and that seismic surveys have taken place for a half-century with no direct evidence that they harm sea animals, commercial fishing or tourism. Studies say they do affect the animals.

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Pleas to Gov. Henry McMaster and a Congressional bill are among other efforts planned by conservation groups to stop offshore seismic testing for oil and natural gas. The groups filed lawsuits Tuesday to derail federal permits for the work.